CircleCI multirepo orb

Support for skipping jobs in multi-purpose repos and monorepos.

This orb uses a CD workflow.

1. Changes are pushed to the integration branch.
2. The integration branch CI job publishes a dev:testing orb and git pushes to the testing branch.
3. The testing branch CI job runs tests. When the tests pass a new patch version of the orb is published, and the change is pushed to master.